Search found 4805 matches

by Jirka
Tue Dec 10, 2019 3:32 pm
Forum: Hydrus 1D
Topic: jump in the value of theta
Replies: 3
Views: 33

Re: jump in the value of theta

First, if you have not actually measured both wetting and drying curves, I do not think that you should be using the hysteresis option in HYDRUS. Second, your other questions: 1. Please, read the manual, where all the models are discribed in detail. 2. Parameter Qm expands the flexibility of the mod...
by Jirka
Mon Dec 09, 2019 6:00 pm
Forum: Hydrus 1D
Topic: jump in the value of theta
Replies: 3
Views: 33

Re: jump in the value of theta

You probably encountered some numerical instability. Perhaps use a different model of hysteresis (e.g., Lenhard et al.). J.
by Jirka
Mon Dec 09, 2019 5:58 pm
Forum: Hydrus 1D
Topic: No data in Time Variable Boundary Conditions and Meteorological Conditions
Replies: 1
Views: 22

Re: No data in Time Variable Boundary Conditions and Meteorological Conditions

You cannot use this option if you do not have values for all required inputs. J.
by Jirka
Mon Dec 09, 2019 5:50 pm
Forum: Hydrus 1D
Topic: Eto Penman monteith vs Eto Hargreaves
Replies: 2
Views: 28

Re: Eto Penman monteith vs Eto Hargreaves

The problem listed above has been fixed a decade ago. My experience is that these two models give very similar results if correct input is used. See an example for a Nevada desert. Hargreaves.png Note that ETo is reference ET, not actual ET, and thus can be larger than precipitation (and almost alwa...
by Jirka
Tue Nov 26, 2019 10:36 am
Forum: HP1 (HYDRUS-1D - PHREEQC)
Topic: How should i enter our data in HP1
Replies: 3
Views: 572

Re: How should i enter our data in HP1

Please note that we have posted a large number of examples and tutorials on the HYDRUS website on how to use HP1, e.g., https://www.pc-progress.com/en/Default.aspx?h1d-tutorials#k6 You can also check this document: Jacques, D., and J. Šimůnek, Notes on HP1 – a software package for simulating variabl...
by Jirka
Fri Nov 22, 2019 11:51 pm
Forum: HYDRUS (2D/3D)
Topic: Dual porosity / Dual permeability
Replies: 1
Views: 572

Re: Dual porosity / Dual permeability

Since in the dual-permeability model there are two mobile domains, one needs to decide into which domain water flows (e.g., infiltration). However, in the dual-porosity model there is only one mobile (and one immobile domain), all water flow to the mobile domain. The interactions between the mobile ...
by Jirka
Thu Nov 21, 2019 2:49 pm
Forum: HYDRUS (2D/3D)
Topic: Nitrate calibration using inverse modelling
Replies: 1
Views: 277

Re: Nitrate calibration using inverse modelling

1. That's up to you whether you run HYDRUS in the direct mode or calibrate the model against your experimental data. I think that it is always better to start with the direct mode and then adjust the parameters in the inverse mode. 2. Note that all these parameters are very clearly described in the ...
by Jirka
Wed Nov 20, 2019 6:29 pm
Forum: HYDRUS (2D/3D)
Topic: BC. options in Hydrus 2D/3D version 1.10
Replies: 2
Views: 285

Re: BC. options in Hydrus 2D/3D version 1.10

I would think so. Although I have to admit that I do not have version 1 installed on my PC any longer since it is more than 10 years since we replaced it with version 2, and later with version 3. J.
by Jirka
Wed Nov 20, 2019 6:27 pm
Forum: Hydrus 1D
Topic: Solute fluxes calculated from obs points
Replies: 2
Views: 297

Re: Solute fluxes calculated from obs points

At the end of the Solute.out file you get solute fluxes for top 3 observation nodes. If you have four observation nodes, then you do not get the info for the last one. While cvBot and Sum(cvBot) reports total solute fluxes, the observation node fluxes, i.e., cv and Sum(cv) are only convective fluxes...
by Jirka
Tue Nov 19, 2019 11:37 pm
Forum: Hydrus 1D
Topic: Errors in solute when surface layer BC is applied
Replies: 5
Views: 498

Re: Errors in solute when surface layer BC is applied

I may have done some minor modifications, which I do not recall. Simply compare the two projects to find out. J.
by Jirka
Tue Nov 19, 2019 6:25 pm
Forum: Hydrus 1D
Topic: Errors in solute when surface layer BC is applied
Replies: 5
Views: 498

Re: Errors in solute when surface layer BC is applied

I do not see any problem. Jl
by Jirka
Tue Nov 19, 2019 3:24 pm
Forum: HYDRUS (2D/3D)
Topic: Simulating Root Water Uptake with Root Growth model using Hydrus 2D
Replies: 9
Views: 713

Re: Simulating Root Water Uptake with Root Growth model using Hydrus 2D

Currently, there is not. I do not have time for that. One could perhaps hardcode something for this specific geometry, but I do not see myself coding something for general geometries. Note that you can manually edit the Domain.dat (a text file of the binary Domain.in file) file externally, using, e....
by Jirka
Tue Nov 19, 2019 1:49 am
Forum: Hydrus 1D
Topic: Errors in solute when surface layer BC is applied
Replies: 5
Views: 498

Re: Errors in solute when surface layer BC is applied

Not without seeing the project. J.
by Jirka
Mon Nov 18, 2019 11:27 pm
Forum: HYDRUS (2D/3D)
Topic: Simulating Root Water Uptake with Root Growth model using Hydrus 2D
Replies: 9
Views: 713

Re: Simulating Root Water Uptake with Root Growth model using Hydrus 2D

The root growth module with multiple plants has not been intended to work on sloped surfaces. That's something that would have to be developed as a new option. J.
by Jirka
Mon Nov 18, 2019 8:53 pm
Forum: HYDRUS (2D/3D)
Topic: Simulating Root Water Uptake with Root Growth model using Hydrus 2D
Replies: 9
Views: 713

Re: Simulating Root Water Uptake with Root Growth model using Hydrus 2D

If you click with the right-mouse button on the HYDRUS icon, you get a pop up menu. From this pop-up menu select "Properties". Under the Tab "Shortcut" you can see the fields "Target and "Start In". These fields give you the path where HYDRUS (the program itself, not its projects) is installed. You ...